how do you get the orange heart on harvest moon?

You're looking at the hearts in the Character Section of the Assets menu. Those hearts will always remain Red and Green. Red means they are available for marriage, Green means it is just a villager.

When you speak with a marriage candidate they will have a small heart in the corner of their dialog box. It starts out Black. Once the person likes you more the color will change. It goes Black, Purple, Blue, Green, Yellow, Orange and finally Red.

You get different colored hearts by making the person like you more. The best way to do that is to give them a gift they like once per day.

In harvest moon games coloured hearts are used to describe the feelings of a bachelor/bachelorette towards you. As the feelings grow deeper so, the colour of the heart changes step-by-step. In harvest moon ds sunshine islands the order (ascending) is:

Black- least amount of feelings.

Purple

Blue

Green

Yellow

Orange

Red- most amount of feelings.

When the person you like in the game has purple,blue and yellow hearts, you can trigger 1 heart event for each of these hearts and if you answer properly you can trigger an orange heart event. It's a little bit surprising that you got the red heart and not the orange. Still, try triggering the three heart events and answer properly and you might get the orange heart/event.

the coulored hearts are the level of affinity a girl, or a boy, depends of your genre, has for you. red is the highest and black is the lowest. If you have a orange heart you can buy a blue feather whitch is a object you need to get married. To get married you have to have the character you want to marry whith a red heart, have a couples bed(bed big enought for 2 peolple), have whatched all the heart scenes which are scenes you can whatch in each heart level in a certain place ate a certain day at a certain time.

Those are the basics of hearts.

PS: try and get Harvest Moon Grand Bazaar. It's harder than the others but way more fun.

the color of the heart is the Heart Point Level. each person who is eligible for marriage will have a heart marker on their portrait. To increase the color of the heart marker you will need to do favorable things, such as talk to the person daily and give gifts. There are 7 color stages you must progress through before the person will accept your marriage proposal.

Black → Purple → Blue → Green → Yellow → Orange → Red

When your potential mate has reached a purple, blue, and yellow heart colors you can trigger Heart Events. There is also an extra orange Heart Event you can view if you choose specific event answers through the previous three Heart Events in order to reach the orange one. You must view at least the purple, blue, and yellow events before marriage.

dude there is no orange heart event!!!